Railway-traffic-controlling system



3.. V. LEWIS RAILWAY TRAFHC CONTROLLING SYSTEM,

Q Z V 111s ATTORIVH.

MENTOR:

2 SHLEFS-SHEETI Patented Feb. 21, 1922.

I B APFLFCATION FILED JAN. 9, I920. LMfifi f,

L. V. LEWIS.

RAILWAY TRAFFIC CONTROLLING SYSTEM.

APPLICATION FILED JAILS), I920.

Patented Feb. 721, 1922.

2 SHEETS-SHEET 2.

mmvm/a' l EGZ M,

LLOYD V. LEWIS, OF WILKINSIBURG, PENNSYLVANIA, .ASSIGNOR- TO THE UNION S'l/VI'I'CII & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A. CORPORATION OF PENNSYLVANIA.

RAILWAY-TRAFFIC-CONTROLLING SYSTEM.

Specification of Letters Patent.

Patented Feb. 21, 1922.

Application filed January 9, 1920. Serial No. 350,322.

T 0 all whom it may concern:

Be it known that I, LLOYD. V. Lewis, a citizen of the United States, residing at l-l ilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful lmprm'cments in Railway-Trafiic-Controlling Systems, of which the following is a specification.

My invention. relates to railway trafiic controlling systems, and particularly to tems of the type wherein alternating current is supplied to the trackway for the control of suitable governing apparatus car ried by the cars or trains.

In one system of'the type mentioned, it has been proposed to employ the usual track circuit current, that is, the current which energizes the track relays, as one of the currents for controlling the train-carried governing apparatus, the train governing apparatus being cont-rolled by this current through the medium of receiving appliances at the front end of j the train. When this is done, it is obvious that the source of track circuit current must always be-connected across the track rails ahead of a train.-

In the case of a double track railroad wherein trahic on each track normally moves in one direction only, this requirementis readily met in so far as movements in the normal direction are concerned, because the source of track circuit current for each section .of track is then connected across the rails at the exit end of the section in accordance with standard practice in automatic block signalling. (in roads of this kind, however, it is sometimes necessary for trains to move in opposition to the normal direction of traffic, and in such instances with only the trackway apparatus thus far mentioned the train would not receive track circuit current. One feature of my invention is the provision of means located in the trackway for connecting an auxiliary source of 1 track circuit across the rails of each section at what is normally the entrance end of the section, to permit train movements in opposition to the normal direction of tratiic.

in systems of this type it has also been proposed to supply asecond, or line circuit current, to the trackway which current ooacts with the track circuit current to control the train governing apparatus. This line circuit current is supplied to only the rear port-ion of each section when the section. next in advan is occupied, and so it follows that when a train moving against the normal direction of trafiic enters a section it will not receive line circuit current until the rear end of the train has passed out of the adjacent section. Another feature of my invention is the provision of means for at times supplying line circuit current to each section throughout the entire section, regardless of conditions in any other section, so that a train moving against the normal direction of tral'hc may pass through the section without restriction.

I will describe two forms of trackway apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a diagrammatic view showing one track of a double track railway equipped with trachway apparatus embodying my invention, and Fig. 2 is a view showing a modification of the trackway apparatus also em;

bodying my invention.

Referring first to Fig. 1, the reference characters 2 and 2 designate the two traiiic rails of a railway track over which trafiic normally moves only in the direction indicatcd bv the arrow. These rails are divided by insulated joints 3 into a plurality of successivo sections, of which only two complete sections A-B and B-G are shown in the drawing.

Each track section is provided with a track circuit comprising as usual the track rails of the section, a source of alternating current connected across the rails at the exit end of the section, and a track relay connected a ross the rails at the entrance end of the section. As here shown, the source of current for each track circuit is a transformer designated by the reference character E With an exponent corresponding to the location, the secondary of which transformer is connected across the rails through a reactance ll) and the primary of which is constantly connected through a pole-changerP with the secondary of a transformer designated D with an exponent corresponding to the location. The primary of each transformer D is connected with transmission line which is supplied with alternating signal current by a generator G. T he act; ray ror which rotor controls three contacts '7, 8 and 9., The stator winding 4: is normally connected with the track rails, as hereinafter explained, whereas thewinding- 5 is constantly supplied with. alternating current from the secondary ot' the adjacent transformer It follows that contacts 7, 8 and S of each relay willhe swung to the. right or to the accordine as current of one relative "t er other is supplied from the rack c rcuit to the stator winding 4-, and hat these contacts will .rest in the vertical iosition when the supply of current to the winding t 'llhe relay contacts 7, 8 and S) are swung to the right when the track circuit is of one relative polarity, which I will call iorinal, and tothe left when the track circuit current is of the other relative polarity, which will term reverse.

Located adjacent the entrance end of each section is a roadside signal designated by the reilerence character 53 with an exponent corresponding to the location. Eachof these signals, as here shown, is of the semaphore ty adapted to indicate Stop, Ca tion or Proceed, according as the here is in the horizontal, the inclined, or the vertical position. Each signal is controlled by thetrack relay for the correspending block through the medium of a caution indication circuit and a proceed indication circuit. Considering signal S for ei-fample, the caution indication circuit (which is open in the drawing) is from the secondary of transformer D through wires 11. and 12, left-hand point of contact 7 of relay T wire 13, operating mechanism of signal S wire 14, left-hand point of contact 8 of track relay T and wires 15 and 16 to the secondary of transformer T The proceed indication circuit is from he secondary of transformer T through. ire 1 and 12. 2, right-hand point of contact of traclr. relay operating mechanism f signal S, wire let, right-hand point of wont-act 8, and 15 and. 16 to the sec nc. of transformer D. It will be seen,

weitcre. that ""1 l .12 indicates caution or .clt relay T is enernormal direction. vrhich is included in cperated by the signal 2 in. advance in such of the current sup nerinal when the or caution, and re- It will track circuit c i is supplied to th 1:3 :11 01% an occupiecircuit current r incl 1 up ied the section in t e rear i an unoccupied se have that winding of each relay is nerinally connected with the r. oi the corresponding section at the entrance. end of the section. liileans are provided, however for times disconnecting this lay winding from the track rails and con necting a source of alternating current with. the rails in its place, and. this means it w now describe.

Located adjacent the entrance end of section is trafiic direction relay, design H with an exponent corresponding to location. Each of these relays is employed. to connect the rails at the entrance end 35 the. corresponding section with winding; 4 of the track relay when the trafiic direction relay is dc-energized, and with the second cry of the adjacent track transformer when the traffic direction relay is energized. Considering section B--@, for example, when the trafiic direction relay H is de-a energised, winding 4-. oil relay T is con-:- nected with the rails of the section, the circuit being from the lower rail 2*, through wire 18, back point -20f contact 19 of relay H wire 20, winding 4 of relay T wire 23, back point of contact 22 of relay H ,and wire 21 to the upper rail 2. V'Vhen relay H is energized, however, Winding i of track relay T? is disconnected from the rails of section l3--C and the secondary of trans former E is connected with these rails the. circuit being from the lower rail 2, through wire 18, front point of contact 19 of relay 19 H wire 26, secondary of transformer E reactance 2-5, wire 2%, front point of con. tact 22 of relay H and wire 21 to the upper rail 2. The function of each of the @ther traffic direction relays H is the same as tha tfl10.-.

controller K comprises a manuallyoperahle' lever 32 which operates two "contacts 27 and 28. Nhen the lever 32- is in the posi tion shown, which I will term the normal position, contacts 27 28 are open, "so that the traflic direction relays H- arena. energized, but when handle 32 is swan-gm the right, to what, it will term its reverse position, the contactsjoperated thereby are closed, so that relays H II", and H" become energized.

As long as traffic is to proceed along the raillay track in the normal direction, that is, in the dirgction indicated by the arrow,

circuit controller K is lett in the position shown, so that the trailic direction relays are (lo-energized. The operation of the system is then in accordance with usual practice, so that no detailed explanation is required. Sufiice it to say, that at such times a source of alternating current is connected across the rails of, each section at the exit end of the section, and a track relay is connected across the rails at the entrance end of each section. When a train movement in the direction opposite to normal is desired, circuit controller K is reversed, whereupon the trafiic direction relays II hecome energized, so that a source of alternating current is connected across the rails of each section at wvhat is normally the entrance end of the section.

Each track section is provided with two line circuits, one of which extends from the entrance end to an intermediate point 34 and the other of which extends from the intermediate point 34 to the exit end of the section, these two line circuits being termed the rear and the forward circuits respectively. As Shown in Fig. 1. each line circuit includes the two track rails in multiple,

the current being supplied to the rails ofeach section through resistances 33, 34 and 35 which are connected across the rails at the entrance end, the intermediate point, and the exit end of the section, respectively. Again considering section B-C, therear line circuit for this section is from secondary 36 of a transformer M through wire 37, contact 9 of track relay T, wire 38 to the middle point of resistance 33. thence through the two track rails 2 and '12 in multiple to resistance 34. and from the middle poilit of this resistance, through wires 39 and 40 to the secondary 36 of transformer M The primary of transformer M is constantly supplied with current frhm the secondary of transformer D, the primary of which, as has been said, is connected with the transmission mains F. Track relay contact 9 is closed only when the relay is de-energized, and, consequently, current is supplied to the real line circuit only when section B-C is occupied by a car or train, or when track relay T is disconnected from the rails by trailic direction relay H The forward line circuit for section B-C is from secondary 41 of transtormerM through wires 42 and 39, to the middle point of resistance 34, thence through the two track rails in multiple to resistance 35, and from the middle point of this resistance through wires 43 and 44, contact Q, and wires 45 and 46 to secondary 41 of transformer M. Contact C is operated by signal S in such manner that this contact is closed when the signal indicates proceed or caution, but open when the signal indicates stop. It will be seen, therefore, that so far as the line circuit just traced is concerned, current is supplied thereto only when signal S indicates pioceed or caution. This circuit is provided with a branch, however, around contact Q,

t at the trackway apparatus here shown is intended for co-operation with train-carried governing apparatus which operates in the following manner: When the train is on a portion of track which is supplied with track circuit current of normal polarity and also with line circuit current, the governing apparatus permits the train to travel at vhigh speed, such as milespcr hour. \Vhen the portion of track occupied by the train is supplied with track circuit current of reverse polarity and also with line circuit current, the'governing apparatus prevents'the. train from proceeding at more than an intermediate speed, such as 35 miles per hour; but when the tl'aimenters a portion of track from which the supply of either track circuit or line circuit current is discontinued, the governing apparatus prevents the train from proceeding at more than a low speed, such as 10 miles per hour. One form of governing apparatus which will co-opcratc in this manner with the trackway apparatus here shown, is illustrated and described in an apilication filed by me in the United States atent Ofiice onNov. 1, 1918, Serial No. 263607, for railway trafiic controlling systerns;

The operation of the entire apparatus is as follows: i

I will first assume that circuit controller K is in the position shown, so that traflic direction relays H are de-energized, and I will also assume that the stretch of track shown in the drawing is unoccupied and that a train moving in the direction indicated by the arrow enters the stretch. As this train enters section A-B, it tie-energizes track relay T so that contacts, 7, 8 and 9 move/to their intermediate positions. The opening of contacts 7 and 8, of course, causes signal S to move to the stop position. The movement of contact 9 to its intermediate position closes the rear line circuit for sect-{on A--B, so that line circuit current is suppt ied to the fit-*B from transformer rails of this section between resistances 33 and 234i. llnasmuch as signal S is in the proceed position, track circuitcurrent of normal polarity is supplied to the rails of section l3, and line circuit current is supplied to the rails of this section between resistances 3 1 and 35, that is, to the forward line circuit for the section. It follows, therefore, that the train can proceed through section A-B at miles per hour or less. The operation of the apparatus in section lB-C as the train passestherethrough is the same as that of tee apparatus in section A-B, and hence it will be understood without further explanation.

I will now assume that while the first train is in section B-C, a second train enters section A-B. Signal 53 is then at stop, so that track circuit current of reverse polarity is supplied to the rails of section A ll. (ontact Q operated by si nal ti isopen, so that line circuit current is not supplied to section i l--13 between resistances 2H- and 35. As the second train passes the point A, it will receive line circuit current and it will also receive track circuit current of reverse polarity, so

that this train will incur a brake application if it exceeds a speedof 35 miles per hour while between resistances 33 and 34:. After passing resistance 34., the train will cease to receive line circuit current, and, consequently, it will incur a brake application if it exceeds 10 miles per hour. ..f this second train passes signal S while the latter is still at stop. it

will fail to receive track circuit current, because such current is shunted by the wheels and axles of the first train, and, consequently, the second train will still be compelled to proceed at a speed not exceeding 10 miles per hour.

I will now assume that, owing to an emergency condition, it is necessary for a train to pass over the stretch of track shown in the drawing in the direction opposite to that ii";- dicated by the arrow. The ope 'ator in tower J then swings circuit controller l: to the reverse position, thereby energizing all of the trailic direction relays ll. Each of these relays then disconnects winding 4 of the adjacent track relay from the rails of its track section and connects the adjacent transformer E with the rails in place of such winding. The track relays thus become (la-energized, so that the signals S more to the Hl'i'YllPOSltlOll. The polarity of the current supplied to the left hand end of each section is then normal. Each relay l-l also closes the forward line circult for the section to the left of the rcla y regardless of traffic conditions extraneous to the section. It follows that a train equipped with apparatus such as that described hereinbefore can then proceed along the track in the direction opposite to that indicated by the arrow at a speed of miles per hour or less, although, conrse such train will have no protection either b the roadside signals 01 by the controlling currents received from the track rails. When it is desired to restore the apparatus to the condition corresponding to the normal direction of traffic, circuit controller K. is returned to its normal position, thereby de-energizing all of the traffic direction relays H. Eachof these relays then disconnects the adj aoent transformer E from the rails of the section to the right and connects the adjacent track relay T with the rails of this section. Each signal S then returns to the proceed position, so that the apparatusis again in the condition in which it is shown in the drawin Referring now to Fig. 2, the apparatus shown herein is the same as that shown in Fig. 1, except as follows:

The main difference between the two views is that in Fig. :2 the line circuits include auxiliary conductors 54. and 546* located in the trackway instead of the two track rails as in Fig. 1. These line circuits in Fig. 2 are supplied with current by a secondary 50 on each transformer D. Considering, section l-C, for example, the forward line circuit is from secondary 50 of transformer I)", through wire 51, wire 52, contact Q wires and (31, auxiliary conductor 54-, wire 55, and common wire 0 to secondary 50 of transformer D? This circuit is provided with a branch around contact Q, which branch is from wire 51, through contact 48 of traflic direction relay H and wire 58 to Wire 61. The rear lin'ecircuit for section B-C is from secondary 50 of transformer D9, through wire 56, auxiliary conductor 54:, and common wire 0 to the secondary 50 of transformer D".

it will be seen that current is always sup plied to the roar line circuit, and. that when, traltic is in the nmxmal direction the supply of current to the forward line circuit is govcrned by signal S for the block next in advance. When tratlic is reversed, however, that ii, when relays H are energized, current is supplied, to the forward line circuit regardless of traflic conditions extraneous to the section.

T he apparatus for supplying track circuit current to the rails of each section is the same as in Fig. 1, eiurept that the circuit for the primary of each transformer E is taken through pole-changing contacts 59 and 60 of the adj accnt trafiic direction relay H. (See relay lli) In Fig. 2 the traffic direction relays H are connected in series instead-elf. in multiple as in Fig. 1. The circuit for these relays, when circuit controller K is reverse 5 is from the secondary of. transformer Qil through contact 28, wire 30, relay H wire 30", relay H wire 30", relay H4, wire 31 and contact 27 to the secondary of transformer 29.

'lhe operation of the apparatus shown in 1 some? Fig. 2 is substantially the same as that of the apparatus shown in Fig. 1, so that a detailed explanation with respect to Fig. 2 is not necessary.

Although I have herein shown and described only two forn of trackway apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departingt'rom the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a section of railway track over which traffic normally movesv in one direction only, a source of alternating current connected across the rails at the exit end of said section, a track relay normally connected across said rails at the entrance end of said section, a signal for the section controlled by said relay, and means for at times disconnecting said relay from the rails and connecting a source of alternating current across the rails at the entrance end of the section.

2. In combination, a section of railway track over which traiiic normally moves in one direction only, a source of alternating current connected across said rails at the exit end of said section for co-operation with trains moving in said normal direction, and means for at times connecting'a source of alternating current across the rails at the entrance end of said section to permit a train movement over the section in opposition to the normal direction of trafiic.

3. In combination. a section of railway track over which traliic normally moves in one direction only, a source of alternating current connected across the rails at the exit end ofsaid section, a track relay and a second source of alternating current located adjacent the entrance end of said section. a

signal for the section controlled by said track relay, and a traflic direction relay for connecting said t'ack relay or said second source of alternating current across the rails.

4. In combination, a section of railway track over which traiiic normally moves in one direction only, a source of alternating current connected across the rails at the exit end of said section, a track relay and a sec-, ond source of alternating current located adjacent the entrance end of said section, a signal for the section controlled by said track relay. a trafiic direction relay for connecting said track relay or said second source of alternating current across the rails. and manually operable means for governing said trafficcontrolling relay.

5. In combination. a section oi railway track over which trafiic normally moves in one direction only, a source of alternating current connected across the rails at the exit end of said section, a track relay normally connected across said rails at the entrance end of the section,'a signal controlled by said relay, a secondsource of alternating current adjacent the entrance end of the section, and manually controlled means for disconnecting said relay from the rails and connecting said second source of alternating current with the rails at the entrance end of the section to permit a train movement over said section in opposition to the normal direction of traffic. 6. In combination, a section of railway track over which traific normally moves in one direction only, a source of alternating current connected across the rails at the exit end of said section, a second source of alternating current adjacent the entrance end of said section, and manually controlled means for connecting said second source across the rails at the entrance end of the section to permit a train movement over said section in opposition to the normal direction of trailic.

7. In combination, a section of railway track over which trafiic normally moves in one direction only, a source of alternating current connected across the rails at the exit end of said section for (:o operation with t'ains moving in said normal direction, a second source of alternating currentlocated adjacent the entrance end of said sectiomand a traffic direction relay for at times connecting said second source of current across the rails at the entrance end ofthe section to permit a train movement over the section in opposition to said normal direction oftrafiic. 8; In combination. a section of railway track over which traffic normally moves in one direction only, a source of alternating current connected across the rails at the exit end of said section, a second source of alternating current located. adjacent the entrance end of said section, a traffic direction relay for at times connecting said second source of current across the rails at the entrance end of the section, and manually controlled means for governingsaid traffic direction relay.

9. In combination, a stretch of railway track over which traflic normally moves in one direction only, said stretch being divided into a plurality of successive sections, a source of alternating current connected across the track rails of each section at the exit end of the section, a track relay normally connected across the rails'of each section at the entrance end of the section, means for each section for at times disconnecting the track relay and connecting the source of alternating currentwith the track rails at the entrance end of the section, and signals for the sections controlled by said track relays. "10. In combixmtion. a stretch of railway trafiic over which 'traflic normally moves in one direction only. said stretch being divided into a plurality of successive sections, a-

source of alternating current connected ecross vile rails of such seceiones of the secilon, a 111 ch relay no heeled. across the as she end of each section, signals the sect-ion con- 'illOllQl by track and means conerolled fi'ono a central poles for discoocclug-the mes relay for each section the rolls thereof and connecting soiu'ce of alternating current the mils of sectionat the end of the l; eombinaiion, stieich of ,over which *crafiic moves in one 'l'l'l'C- lcida. only, source of bins" current connecicd across she rails on" exit end of the section, a

lay for euch'section for COLJQC of alt-err. mg cm'reul' the rails i entrance end of: she seccion, and means controlling all of said trafiic direction relays from a central point.

12, lln combination, sisetch of railway track ovec which luuffic normally moves in one direc'lion, said siietch being divided into i plurality of success sections, e source of current coiiuece across the rails of each the exil; of the section, ireclc relay normally conuecized across the rails of sectionadjacent the euci'ance end of section, for the olled by said track relays, a

iielay for each section fol c1536 snack relay such ene-leofand connecting a source of alnn ting current said rails at the cuof ihe sectic 0; me is for cong'all of 'icusc dissed-on rcelsys a conical. point. In combination, of railway fill; over which braille no; molly moves in one direction only, a, line circuit for said section extending the emi'unce end of the section to an intermediate point in che section and including a source of al'ernatin current, a second line circuit exc -ending; 'fconi said intermediate point lo the exit end section, means controlled by 'tlsific Mons in advance of said section n g current i; v 5' so llllel cui en c to re, cless ti'ailic section. 14. in conihinotio' track over which i one direction only,'a line circuit iuchidiny she ic -v0 track in mul'fple from cnei aice end of the section so an ;diate point in the section, means 01 supplyling current to circuit, a second line circuit including the two era-cl; rails in multiple from said intermediate point to the eiiit'end of the-section, means controlled by sraffic conditions in advance of said section for supplying currenl; to said second line ciscuiu, autimes supplying oi: irailic condi tions extraneous to said seclion.

*reus to said second line circuit egardless 15. In combination, a section of railway track over which tialiic normally moves in one direction only, a line circuit extending from the entrance end of the sectiouto on a source of alternating current, a

cond line circuit fromsaid iniei'mediate point to die exit end of the secion, leanscontrolled by iqi'al'fic conditions in advance of said section for supplying; alternating current to said second line circuit, a traffic direcsion relay, and means controlled by said relay "for removing said lose-mentioned means from control by trailic conditions in advance of the section.

16. ln-conibina'bion, a section of railway track over which traffic normally moves in one direction only, means for supplying line circuit cuiienl; to the two rails of said sec lion in multiple from the entrance end to an intermediate point in the section 011 from the entrance end to the exit end according, to trafiic conditions in advance of the section, and means Poi: ax; limes removing said means from control by traffic conditions in advance of the section and supplying line circuit current to the rails throughout the lengch of the section.

ntermediate point in the section and in-* 1?. ln combination, a stretch of railway said signal indicates proceed but not when it iudicaies-stop, and means for each section for at tunes removing said last-mentioned means from conei'ol by she signal for secx'zion in advance.

18. in combination, a stretch of railway ciacl: over which tx'allic normally moves in one direction only, said stretch being divided into a plurality of successive sections, a signal for each section, a line circuit for each section extending from the entrance end-of lhe section to an intermediate point in the section ar id including a source of alternating current, ""1 second line circuit for each section extending from said intermediate point to the exit end of the section, means for each section controlled by the signal for the section next in advance for supplying alternating current to said coud line circuit when said signal indicates oa'oc/eed but not when a plurality of successive sections, a siga central point.

it indicates stop, a traffic direction relay for each section, means controlled by each traffic direction relay for removing said last-mentioned means from control by the signal for .the section next in advance, and means for controlling said traffic direction relays from 19. In combination, a stretch of railway track-over which traffic normally moves in one direction only, said stretch being di- -vided into a plurality of successive sections,

a signal for each section, a linecircuit for each section extending'from the entrance end of the section to an intermediate point in the section and including a source of alternating current, a second line circuit for each section extending from said intermediate point to, the exit end of the section and including a contact operated by the signal for the section next in advance which contact is closed when the signal indicates proceed but not when the signal indicates stop, abranch for said second line circuit for each section around said signal-operated contact, and means located at a central point forclosing the branch for the second line circuit for each section.

.20. In combination, a section of railway track over which traffic normally moves in one direction only, a source of alternating currentco'nnected with the track rails ad-- jacent'the exit end of the section, a second source of alternating current adjacent the entrance end of the section, a track relay normally connected with the rails adjacent the entrance end of the section, a signal for said section controlled by said track relay, means controlled by traffic conditions in ad Vance of said section for supplying line circuit current to the two track rails in multi ple from the entrance end of the section to an intermediate point in the section or from the entrance end to the exit end of the sec tion; and means for at times disconnecting,

said track relay 'from the rails and connect ing said second source of current with the rails adjacent the entrance end of the section, and supplying line circuit current to the two track rails in multiple throughout the entire section regardless of traffic conditions in advance-of the section.

21. In combination, a section of railway track over which traffic normally'moves in one direction only, a source of alternating current connected across the rails adjacent the exit end of said section, a second source of alternating. current located adjacent the entrance end of the section, a track relay "normally connected across the rails adjacent the entrance end of the section, a signal for said section controlled by said track relay;

a line circuit for said section extending from the entrance end to an intermediate point in the section and including a source .ditions extraneous to the section.

of alternating current, a second line circuit extending from .said intermediate point to the exit end of the section, means controlled by traffic conditions in advance of said section for supplying alternating current to said second line circuit, and means for at times disconnecting said track relay 'from' the rails of the section, 'connecting said second source of current across the rails at the entrance end of the section,

and supplying alternating current to said second line circuit regardless of traffic con- 22. In combination, a stretch of railway track over which traffic normally moves in one direction only, said stretch being divided into a plurality of successive sections,

a line circuit for each section extending from the entrance end 'of the section to an intermediate point in the section and including a, source of alternating current, a second l ne c1rcu1t for each section extend- 111g from said lntennedlate po nt to the exit end of the section, means for each section normally controlled by traffic conditions in advance of the section for su plying alternating current to said second ine circuit, a

traffic direction relay for each section forremoving said last:mentioned means from control by traffic conditions in advance, and means for controlling all of said traffic direction relays from a central point.

23. In combination, a section of railway track over which traffic normally moves in.

one direction only, means normally controlled by traffic conditions in advance of said section for supplying line circuit current, to the section for co-operation with trains moving in' normal direction over the section, and means for at times supplying line circuit cnrrent to' said section regardless tions extraneous to the section to permit a train movement thereover in opposition to the normal direction of traffic.

In testimony whereof I affix my signature in presence of two. witnesses.

LLOYD v. LEWIS. i Witnesses A. HERMAN WEGNER, E. P. GRUM. 

